You would have to find some documentation or instructional video of how to open your computer and locate it, and make sure it's still connected. If it's not something you feel comfortable with, I would take it in somewhere and explain what's happening. Within a few minutes they should be able to tell you if it's something hardware related or a corrupt hard drive (still hardware related, but not what I was getting at).
Can you provide a link the the exact laptop you have?